This invention relates to a composite process cinematography system and method and more particularly to such a system and method which combines the features of projection cinematography and reduced focused imaging.
Process cinematography in general involves the technique of front or dual projection of images onto single or dual reflective screens, respectively. In front projection, an image of a background scene, or the like, is projected, via an angled mirror, onto a screen extending behind an actor to create the illusion that the actor is a part of the scene.
In the dual projection process, a screen is aligned to face the camera and a side screen disposed at a 90.degree. angle to the front screen. An image projected through a semi-reflective, semi-transparent, mirror or window extending at 45.degree. to both screens is reflected and passed to both screens, and the use of mattes or countermattes disposed adjacent the screens enables an apparent depth perception to occur so that, for example, an actor can appear to walk behind an object, such as a building, projected on the screens.
These techniques were less than perfect since, for example, in the dual projection process, the mattes and countermattes require great accuracy in positional alignment and their edges required the tedious application of masking material to obtain an accurate matte blend. Also, the system required a doubling of studio space to accommodate two simultaneous projection throws, and the projector light output was not sufficiently intense to accommodate large reflective screens.
Several improvements have since evolved. For example, the size of the side screen was reduced by utilizing a field lens between the latter screen and the countermatte. Also, the restrictions of the matte outline adjustments were overcome by utilizing compatible glass sheets on which were delineated the required shapes for the matte and countermatte so that the blend of the interlocking mattes could be viewed through the camera and adjusted through hand-drawn additions and removals of black masking paint applied to the matte glasses.
However, these techniques still required the utilization of a large glass matte for the front screen and, in addition, required that the latter matte be a substantial distance (up to 20 feet) from the camera, entailing much footwork and time delays between setups. Also, it was difficult, if not impossible, to create any effects that would be otherwise possible if the mattes and countermattes could be occluded, or moved, at a rapid rate.
Also, these types of techniques required light intensity and color correction devices since the light reflected from the smaller side screen is at much greater intensity than the principle screen.